Timing device



y 26, 1932- M. L. NELSON 1,868,989

TIMING DEVICE Original Filed Jan. 9, 1926 l0-5ECOND CAM I I I 402 5-5ECOND CAM 4/0 Patented Jul 26, 19222 UNITED STATES PATENT oFricE MARTIN L. NELSON, OF PARK RIDGE, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS,

' lO ASSOCIATED ELECTRIC LABORATORIES, INC., OF CHICAGO, ILLINUIS, CORPORA- TION OF DELAWARE TIMING nnvron Original application filed January 9, 1926, Serial No. 80,167, Patent No. 1,729,854, dated October 1, 1929. Divided and this application. filed August 29,1929. Serial No. 389,169.

uary 9, 1926, which issued as Patent No.

1,729,854, 0a. 1, 1929. r Referring now to the single sheet of draw- 1 ing, the timing device TD shown therein is the same as the timing device TD shown at the left in Fig.5 of the drawing in my above mentioned application.

:In the application above referred to the timing device is used to cause a specified operation to take place by the closure of contacts 410' or the contacts 411 in case the equipment with which it is associated remains in a given condition for more than a i prescribed length of time.

Referring now to the drawing, the timing device TD includes an armature 404 associated with the clutch magnet 405, the ratchet segment 403 and cams 401 and 402. The cams 401 and 402 are assembled rigidly with the ratchet segment 403 (being shown apart in the drawing for the sake of clearness), and the assembly is arranged to rotate on a pivot at the upper end of the armature 404.

There is a shaft 406 which is constantly rotated. This shaft is common to a plurality of timing devices, the timing devices being arranged side by side along the length of the shaft. This rotating shaft 406 is provided with wings 407 and 403.

In its normal position, the segment 403 is out of reach of the wings 407 and 408 of the common shaft, and the teeth of the segment 403 are out of reach of the retaining spring 409. Then the clutch magnet 405 is energized, however, by an application of ground potential to conductor 2, as, for example, by an operation of the contact spring 322, the armature 404 is attracted and moves to the right, bringing the segment 403 in such a position that it registers with the retaining spring 409 and is within reach of the wings 407 and 408. In this position of the segment 403, thesaid segment is advanced one step in a counterclockwise direction each time one of the wings of the shaft rotatesv by the teeth of the segment. In the operated position of they armature 404, the cams .401 and 402 are v likewise carried to the right so that they are in a position to operate the associated springs whenithe segment 403 has been advanced a sufficient number ofsteps.

lVhen the clutch magnet 405 .deenergizes, the armature 404 moves to the position shown in the drawing, whereupon the teeth of the segment 403 are disengaged from the retaining spring 409 with the result that the segment 403 and the cams 401and402, operated g by, gravity, assume the position shown in the draw ng. r it p i Incase the ground potential is maintained on conductor 2 for a sufiieient length Oftime, the five second cam 403 closes the contact springs 410'at the end of approximately five seconds, thereby bringing ina signal or performing any operation that may be desired.

In case the conductor 2 remains grounded still longer, the contact springs 411 are operated momentarily by the projection on cam 401 at the end of approximately ten seconds, bringing in an additional signal or causing an additionaloperation, all depending upon the construction of the apparatus with which the timing device is used; 7 V

It will be understood of course thatithe time mentioned in connection with the operation ofthe timing device is purely arbitrary and that the timing device may be used to time operations of any convenient or desired length. V

It is tobe notedalso that the shape of the cams'is a matterthat may bedetermined in accordance with the use to which the timing device is to be put. It will be noted that the five-second cam is so shaped that the springs 410, once operated,'remain operated until the timing device is released, whereas the spring contacts 411are operated only momentarily by thecam1401.

In case the ground potential is maintained on conductor 2 until the timing device is fully operated, the operation of the segment 403 ceases when the last tooth thereof has been engaged and moved by one of the wings of the shaft 406, and the assembly rotates in a clockwise direction to the position shown in the drawing when magnet 405 deenergizes upon a subsequent removal of the ground potential from conductor 2.

WVhat is claimed is.

1. In a timing system, a toothed driving shaft having an untoothed portion, a toothed rotatable member out of reach of said toothed shaft, a clutch magnet for bringing said member into the reach of said shaft whereby said member is rotated, and a normally ineffective retaining pawl for said member to retain the same in its attained rotary position and effective when said member is moved into reach of said shaft.

2. In a timing device, a driving device, a

movable member out of reach of said device,

a clutch magnet for bringing said member into the reach of said device whereby said member is driven intermittently, and a retaining pawl for said member to retain the same in its attained position, said pawl being v, arranged to be lIlQflGCtlVG when said member is out of reach of said device and effective when said member is moved into reach of said device. a

3. In a timing device, a toothed timing member arranged to be driven in a given direction and at a predetermined rate to denote elapsed time, a driving device arranged to make contact with the teeth of said timing member at predetermined intervals to drive said timing member in said given direction, means for bodily moving said timing member in a coordinate direction into reach of the driving device to start the timing operation, and a retaining device arranged to retain said timing device in its attained position between successive contacts made with said timing member by said driving device.

4:. In a timing device, a timing member arranged to be driven step by step to denote elapsed time, a rotating driving device having a projection thereon for stepping said timing member each time the driving device makesja revolution, means for bringing said timing member and driving device into associatlon with each other to start a timing operation and for moving them apart after the timing operation has been performed, and means arranged to hold said timing member in its attained position during the timing operation and to allowv the timing member to restore automatically when the timing member and drivlng device are separated at the end of a timing operation.

In witness whereof, I hereunto subscribe my name this 27 thrday of August, A. D. 1929.

. MARTIN L. NELSON. 

